Medical Notes

Neurology Articles

Extrapyramidal Signs

Extrapyramidal signs and symptoms occur as a result of pathology in the basal ganglia. They should be differentiated from pyramidal signs, which occur following an upper motor neurone lesion.

Some of the dyskinesias (abnormal movements) which occur following extrapyramidal pathology or treatment with antiparkinsonian medications are discussed in more detail in the 'Other movement disorders' article. More detailed descriptions of progressive supranuclear palsy (PSP) and Multiple system atrophy (MSA), referred to in this article, can also be found there.

This article focusses on examination of a patient with suspected parkinsonism and some associated signs and symptoms.

General inspection

Look for:

Walking aids

Hypomimia (reduced facial expression)

Stooped posture (in PD)

Resting tremor. This is often described as "pill-rolling" and is frequently exacerbated by high emotions. In Parkinson's disease, the tremor usually starts asymmetrically, commonly in the hands and/or feet. Later in the disease, tremor may spread to all four limbs, and sometimes the face (eg. the lips or chin). Patients with drug-induced parkinsonism are more likely to experience a symmetrical tremor

Choreoathetosis. These abnormal movements are often caused by Parkinson's medications. For a more detailed description of this and other dyskinesias, see 'Other movement disorders'.

Focussed cranial nerve exam

Olfactory nerve

Sense of smell may be one of the first functional losses evident in Parkinson's disease.

Oculomotor, trochlear and abducent nerves

Examine eye movements for presence of a vertical gaze palsy. This is a common feature of the parkinsonian syndrome Progressive Supranuclear Palsy (PSP). Patients may have difficulty looking down voluntarily. However oculogyric downward gaze is preserved. This can be demonstrated if you ask the patient to fix their gaze on a point straight ahead while you move their head back (extending the neck).

Trigeminal and facial nerves

The (primitive) glabellar reflex is often present and prolonged in parkinsonian patients. It is elicited by repeatedly tapping the forehead (between the eyebrows), from outside the field of vision. Blinking after the initial 2-3 taps is normal. However failure to supress the reflex after subsequent taps is indicative of pathology.

Pseudobulbar palsy

This can be a feature of PSP. It is caused by lesions in the upper motor neurons which synapse on the cranial nerves in the medulla (bulb) of the brainstem (hence pseudo-bulbar, as damage is not to the cranial nerves themselves).

Abnormal, labile affect - crying or laughing inappropriately, and alternating between the two

Limbs

Tone

Test for evidence of 'lead-pipe' rigidity. The joints will resist movement in all directions. When rigidity is combined with tremor, the effect is sometimes called 'cogwheeling'. This is best elicited at the wrist. Hold the patient's hand (as if in greeting), moving it in a circular motion while steadying their wrist with your other hand. In the presence of cogwheeling, the motion will be jerky. Cogwheeling can be brought out more by asking the to patient to simultaneously move their other arm up and down (synkinesis).

Bradykinesia

Ask the patient to touch their thumb to each of the fingers in that hand, and to make the movements as big as possible. Parkinsonian patients generally perform this slowly, with progressively smaller amplitude of movement as they complete the task.

Function

Ask the patient to write their name. Look for evidence of small spidery handwriting (micrographia), particularly writing which gets smaller across the page as the patient writes

Cerebellar function

The cerebellum may be affected in Multiple System Atrophy (a Parkinson-plus syndrome). Test for past-pointing and dysdiadochokinesis:

Finger-nose test for dysmetria- ask the patient to alternately touch their nose and your index finger. As the arm is outstretched to touch your finger, the patient's finger might veer from side-to side (intention tremor) or overshoot (past-pointing).

To test for dysdiadochokinesis, ask the patient to alternately pronate and supinate their dominant hand on the back of their non-dominant hand. Test the non-dominant hand in a similar way. Rapidly alternating these movements will be difficult in patients with cerebellar dysfunction.

Autonomic function

Another feature of MSA may be autonomic dysfunction:

Test the patient for postural hypotension by taking their sitting and standing blood pressure.

Examine the mouth for evidence of reduced salivation, or simply ask the patient if their mouth feels dry

Ask about bladder problems

Ask about constipation

Ask about excessive or reduced sweating

Postural instability

With the patient facing away from you and having explained what you are about to do, pull back hard on their shoulder so as to unbalance them. Normally, people will regain their balance by taking 2-3 steps backwards and will not fall. Parkinsonian patients often need to take more steps than this, or will fall back.

Stand close behind the patient while performing this manoevre and keep your hands by their shoulders in order to prevent the patient falling to the ground.

Gait

Ask the patient to walk a short distance, then turn and walk back. Several features are characteristic of a parkinsonian gait:

Difficulty initiating movement (hesitancy)

Small, shuffling steps

Festination, where the patient speeds up as they walk

Reduced arm swing

Turning en bloc

Extra questions

Dementia with Lewy-Bodies is commonly present in patients with parkinsonian symptoms. Ask about visual hallucinations as these are present in 75%, often featuring animals or people. Many sufferers do not find these hallucinations threatening, and may have good insight as to their origin. An MMSE is a useful initial screening tool for neuropsychological changes.

REM-sleep behaviour disorder is another common problem in parkinsonian patients, often appearing many years before the onset of other symptoms. Patients act out their dreams while asleep, and may kick or thrash out, potentially harming themselves or their partners. The patient will not be aware of the movements at the time, so a collateral history from a sleeping partner is helpful.